OK, I got everything from the description except the hammer out so that changes that number to 135 from 127. That raises the ratio to 5.58. I remeasured the displacement as carefully as possible and got pretty much 6 (36/6). Going to the tip of the hammer pushes it up to 5.87 but you have to wonder about the meaning of having to tweak each number and what that means. Ea Ra Ratio Key 240 128 0.53 Wippen 63 83 1.32 Action Ratio Shank 17 135 7.94 5.58 David Love www.davidlovepianos.com -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Ron Nossaman Sent: Saturday, September 22, 2012 8:57 AM To: pianotech at ptg.org Subject: Re: [pianotech] Action ration measuring On 9/22/2012 10:30 AM, David Love wrote: > Using your method (if I understood it correctly) I get the following > on my action model. As unclear as my description was, I put the attached jpeg together. That might change things. >The measurement of dip to hammer travel yields 37/6 or > 6.16. Interestingly, your method of measuring the levers yields a lower > AR than my method (measuring the key to the end and the wippen to the > jack center pin) yet moving the dip measurement 20 mm in from the end of > the key will, of course, produce a higher action ratio than mine > measuring at the end of the key. Wip out and hammer out is different too. Hammer out, for instance, is about half way between center pin to molding center, and center pin to strike point. >Perhaps these things are action > specific, though it's hard to imagine why. I don't see how they could be either. Check the drawing against my poor description of measurement points, and see what you get. ??? Ron N -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20120922/57089687/attachment.htm>
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